Scavenging air cooler



April 20, 1965 J. M. HARING SCAVENGING AIR COOLER Filed Aug. 7, 1965 3 Sheets-Sheet 1L dab/7 M. Har/Q9' INVENTOR. I 13% 7 W .April 20, 1955 J. M. HARING 3,179,092

SCAVENGING AIR COOLER Filed Aug. 7, 1963 3 Sheets-Sheet 2 ,4 Tron/v5 ys April 2o, 1965 Filed Aug. 7, 1963 J. M. HARING scAvENGING AIR COOLER 3 Sheets-Sheet 3 5 l ow f4 f INVENT'OR.

United States Patent O 3,179,092 SCAVENGlNG AIR CQGLER .lohn M. Haring, R0. Box 22587, Houston, Tex. Filed Aug. '7, 1963, Ser. No. tltlAS 3 Claims. (Cl. 123-72) rllhe present invention relates to improvements in scavenging air coolers particularly for two-cycle engines.

The beneficial etfects of cooling scavenging air have been known and recognized by owners and operators of two-stroke cycle engines for a long time. These include the elimination of detonation, reduction of fuel consumption, increase of available horse power, reduction of heat rejection to water jacket and the lube oil system, reduction of exhaust gas temperature and reduction of required fuel pressures. `In practice there has been no practical solution to the problem of cooling large quantities of air at low pressure and at high intermittent flow rates within the space limitations available. rFhis is a major reason why scavenging air coolers for two-stroke cycle engines have not been universally accepted. The present invention is directed toward a scavenging air cooler for twostroke cycle engines which provides a solution to this problem of cooling large quantities of air at low pressure and at high intermittent ilow rates within the available space limitations.

lt is therefore an object of the present invention to provide an air cooler for cooling large quantities of scavenging air at low pressure and at high intermittent ow rates for two-stroke cycle engines within the available space limitation.

Yet a further object of the present invention is to provide such a scavenging air cooler which eliminates detonation, lreduces lfuel consumption, increases available horsepower, reduces heat rejection to water jacket and lube oil system, reduces exhaust gas temperature and reduces required fuel pressures.

Yet a further object of the present invention is the provision of an air cooler for cooling large quantities of scavenging air at low pressure and at high intermittent ilow rates to a temperature of less than 140 F. for twostroke cycle engines within the available space limitation.

Yet a further object of the present invention is the provision of such an air cooler for cooling scavenging air of two-stroke cycle engines within the available space limitations which is inexpensive, of simple and rugged construction and which may be readily and easily installed on existing two-stroke cycle engines.

Yet a *further object of the present invention is the provision of such a cooler for scavenging air which cools large quantities of surging air with a minimum of vibration.

Other and further objects, features and advantages will be apparent from the following description of a presently-preferred embodiment of the invention, given for the purpose of disclosure, and taken in conjunction with the accompanying drawings, Where like :reference numerals designate like parts throughout the several views, and where FlGURE 1 lis a fragmentary elevational view, partly in section, illustrating an air cooler according to the invention installed on a two-stroke cycle engine,

FIGURE 2 is an enlarged, perspective view, illustrating the air cooler illustrated in FIGURE 1,

FIGURE 3 is a bottom View of the air cooler illustrated in FIGURE 2,

FIGURE 4 is a sectional view taken along the line 4 4 of FIGURE 3,

FGURE 5 is a sectional view taken along the line SS of FIGURE 3,

FIGURE 6 is a sectional view taken along the line 6-6 of FIGURE 3,

ice

FlGURE 7 is an enlarged, fragmentary, elevational view, partly in section, illustrating the header arrangement at each end of the air cooler.

Referring now to the drawings, and particularly to FlG- URE l, the reference numeral lll generally designates an air cooler according to the invention shown in place on a conventional two-cycle engine. The air cooler lli is secured about the valve opening at the top portion of the scavenging air pump cylinder l?. provided with the piston le connected by the connecting rod to the crank shaft 18 or the engine.

The cooler lill is secured to the upper portion of the cylinder l2 where the valve covers have been removed, as illustrated, and are connected by bolts, not shown. Thus, clean air entering the cylinder l?, through the inlet valves 2li -is pumped through the outlet valves 22 through the air cooler `liti into the inlet 24 passing into the internal cavenging air header 26. The cool scavenging air then passes `through the inlet scavenging air passage Z3 into the cylinder 3b, here shown as ybeing closed by the piston 32 and is exhausted out the exhaust 34j during the scavenging portion of the stroke in the usual manner.

ln installations of two-stroke cycle engines, there is ordinarily a catwalk 36 and a railing $8 which severely limits the space into which an air cooler can be placed for cooling the scavenging air. The air` cooler l@ by its arrangement and combination of parts permits highly eliective cooling of the scavenging air, that is to a temperature of less than F.

While the remaining environmental parts of a conventional two-stroke cycle engine are shown no numerals are applied to these parts as these are conventional, as such do not constitute the present invention, and are eliminated to shorten and simplify the disclosure. Accordingly, no `detailed description of the remaining parts or" the two-stroke cycle engine are deemed necessary or given.

Referring now to FIGURE 2, the air cooler includes a base lill which is generally shaped to t about the opening for the exhaust valves of the cylinder l2 (FlGURE l) which pumps the scavenging air into the engine. The base itl has the outwardly extending peripheral flange l2 provided with the holes 411i through which bolts, not shown, extend for securely bolting the air cooler to the cylinder l2.

The air cooler l@ includes a generally cylindrical body 46, although it may otherwise be shaped., such as square, rectangular and the like, and which is secured to the base lll by the upstanding members t-S and Sii disposed at each end.

The generally rectangular base lll is open throughout its length except for the partition 52 disposed adjacent the exhaust end of the base e@ which is in line with the internal passage within the upstanding member Sti. Thus, air from the cylinder 11.2 (FGURE l) passing through the discharge valves 22 enters into the space Se within the base 40, flows through .the hollow upright member i8 into the body 46 of the air cooler, out through the hollow support member 63 and in-to the exhaust passage 56 of `the base lill.

Disposed at each end of the body 46 are the outwardly extending ilanges :'58 and 6@ to which are secured the langes 62 and 64 of the end covers 66 and o8, respectively, sueh as by bolting as illustrated. Preferably the end covers no and 68 serve as headers for the cooling iiuid and the closure member 66 includes the fluid inlet 'lll and ll-uid outlet 'F2 through which cooling fluid is supplied to the cooler and recirculated from a suitable cool-ing source, not shown. The end closure de with the cooling header passages is best illustrated in FIGURE 4 and the end closure 63 illustrating the cooler header return passages is best seen in FlGURE 6.

Referring now to FlGURE 7, there are disposed at each end of the body d6, a circular support member '7d and '7S which received the tubes 76 and Support these tubes adjacent each end of the body ywhich serve to support the tubes as shown. These support plates 74 are disposed snugly against the Water course members of the headers 66 and 68 for directing flow through the tubes 76 and the seals 77 and 79 are provided to seal off the headers in the heads 66 and 68.

The arrangement illustra-ted is an eight pass cooler in which cooling i'luid is introduced in the inlet 70 and circulated through the cooler eight times and out the outlet 72.

Suitable baffles are provided for causing the air entering the cooler in the inlet 54 to be deflected and to obtain the maximum cooling effect from the cooling fluid being circulated in the tubes 74. This is best illustrated in FIGURES 3 and 5, to which reference is now made. As there shown three baflles 78, Sil and 82 are illustrated. These are generally in the shape of a circular disc general y the size of the inner portion of the cylindrical body du, which disc has been cut into three parts and spaced along the body as shown. These battles also serve the purpose of supporting the tubes at spaced points and assist in eliminating vibration which otherwise would result from the high intermittent llow rates through the cooler 10.

In operation the cooler is assembled by removing the valve cover plate, not shown, and connecting it to the body of the cylinder l2 as previously mentioned. Air drawn into the cylinder l2 through the inlet valves 20 and out `through the outlet valves Z2 flow through the passage 54 into the cooler lil and about the tubes '76 (FIGURES 3, 5 and 7) and out the outlet 56 (FIGURE l) and into the scavenging air inlet 2d into the scavenging air header Ztl, the partition 52 serving to direct the air from the cylinder l2 into the cooler lll as previously explained. Cooling tluid such as Water, enters the inlet 70 into the header 66 and is directed back and forth through the cooler l@ in the tubes 76, all as previously explained. The baflles 78, 80 and S2 (FTGURES 3 and. 5) electively deflect the llow of air through the cooler l0 so that maximum cooling of the air is obtained.

By using Water at normal temperatures, the temperature of the scavenging air exhausting at 3d (FlGURE l) is less than 140 F. This eliminates detonation, reduces fuel consumption, increases the available horsepower, reduces the heat rejection to the water jacket and lube oil system, reduces the exhaust gas temperature and reduces the required fuel pressure.

The construction shown and described substantially eliminates vibration, even though large intermittent low of air is provided.

As previously mentioned7 the air cooler may taire a wide variety of shapes and forms. The tubes may extend lengthwise, transversely, or otherwise of the body of the air cooler and the body of the air cooler may be integral with or 'lush with the base 40 as desired. Bathing should be provided to insure effective cooling of the air and to eliminate vibration and provide strength to the air cooler in view of the large surges of pulsating scavenger air being cooled.

Any desired cooling lluid may be used. In view of its general availability, water is preferred, however7 in some areas, it may be desirable to utilize other liquids or fluids and recirculate them after they have -been cooled by a suitable means.

As many of these coolers may be used with a two-cycle engine as desired, however, the maximum number per engine will be the same as the number of scavenging air cylinders per engine. Under most operating conditions an air cooler for each scavenging piston and cylinder arrangement cools the scavenging air exhausting from the engine to F. and less, which is highly satisfactory.

The present invention, therefore, is well suited and adapted to attain the objects and ends and has the advantages and features mentioned as Well as others inherent therein.

While presently-preferred embodiments of the invention have been shown and described, changes in the form, detail and arrangement of parts may be made which are within the spirit of the invention as deiined by the scope of the appended claims.

What is claimed is:

l. ln an engine provided with a scavenging cylinder, a scavenging cylinder valve communicating with the scavenging cylinder, and a scavenging air inlet into the engine,

a iirst passage in the outer Wall of the cylinder in fluid communication with the scavenging cylinder valve,

a second passage in the outer Wall of the cylinder in fluid communication with the scavenging air inlet into the engine,

a heat exchanger connected to the scavenging cylinder,

said heat exchanger provided with an inlet in fluid communication with the lirst pasage,

and

an outlet in huid communication with the second passage,

2. ln an engine provided with a scavenging cylinder,

a scavenging cylinder valve communicating with the scavenging cylinder, and a scavenging air inlet into the engine,

a llrst passage in the outer wall of the cylinder in fluid communication with the scavenging cylinder Valve,

a second passage in the outer Wall of the cylinder in liuid communication with the scavenging air inlet into the engine,

a heat exchanger provided with a base connected to the scavenging cylinder,

an inlet passage in the base in fluid communication with the first passage, and

an outlet passage in the base in lluid communication with the second passage.

3. In an engine provided with a scavenging cylinder, a scavenging cylinder valve communicating Iwith the scavenging cylinder, and a scavenging air inlet into the engine,

a first passage in the outer Wall of the Icylinder in lluid communication with the scavenging cylinder valve,

a second passage in the outer wall of the cylinder in luid communication with the scavenging air inlet into the engine,

a heat exchanger provided with a base, said base being secured to the scavenging cylinder and about the lirst passage and the second passage, and

a partition in the base providing a scavenging air inlet in fluid communication with the lirst passage and a scavenging air outlet in liuid communication with the second passage.

References Cited by the Examiner UNITED STATES PATENTS 1,537,128 5/25 Mayer 123-72 1,821,662 9/31 Muller ,ve.- 12S-,72

FOREIGN PATENTS 940,064 5/48 France.

FRED E. ENGELTHALER, Primary Examiner. 

1. IN AN ENGINE PROVIDED WITH A SCAVENGING CYLINDER, A SCAVENGING CYLINDER VALVE COMMUNICATING WITH THE SCAVENGING CYLINDER, AND A SCAVENGING AIR INLET INTO HE ENGINE, A FIRST PASSAGE IN THE OUTER WALL OF THE CYLINDER IN FLUID COMMUNICATION WITH THE SCAVENGING CYLINDER VALVE, A SECOND PASSAGE IN THE OUTER WALL OF THE CYLINDER IN FLUID COMMUNICATION WITH THE SCAVENGING AIR INLET INTO THE ENGINE, 